Asphalt manufacture



Patented June 23, 1942 ASPHALT MANUFACTURE Robert E. Burk and Charles H.Whitacre, Cleveland, Ohio, assignors to The Standard Oil Qompany,Cleveland, Ohio, a corporation of Ohio No Drawing. Original applicationNovember 23,

1936, Serial No. 112,348. Divided and this application March 23, 1938,Serial No. 197,680

3 Claims.

In manufacturing asphalt, it has been the custom to blow the petroleumresiduum with air, and maintain the temperature at about 300-500 F. Theprocedure is very tedious, requiring a long duration of action in orderto bring the material to useable characteristics of high melting pointand low penetration. Although enormous quantities of oxygen are broughtinto relation with the hydrocarbon material, there is not a greatincrease in the oxy gen content, and the action is largely adehydrogenation and conjoining of hydrocarbon molecules. We have nowfound that particularly effective action in thickening up the materialtodesirable penetration and melting point can be obtained without thecumbersome and time-consuming air-blowing, and the entire operating canbe completed in a fraction of the time heretofore necessary, theproducts being also superior.

To the accomplishment of the foregoing and related ends, the invention,then comprises the features hereinafter fully described, andparticularly pointed out in the claims, the following descriptionsetting forth in detail certain illustrative embodiments of theinvention, these being indicative however, of but a few of the variousways in which the principle of the invention may be employed.

The stock to be worked up, a heavy petroleum oil residue, which wedesignate the residuum, is in accordance with the invention heated withair, and a small or catalytic-amount of a polymerizing catalyst. Thetemperature of treatment may be 225-450 F. Desirably, the material issuitably stirred or agitated. The time of treatment is short, as forinstance 20 to 300 minutes. As catalysts, we employ halides, as ferricchloride, aluminum bromide, aluminum chloride, aluminum iodide, halidessimilarly of copper, tin, zinc, antimony, arsenic, boron, titanium,etc., hydroxides of sodium, potassium, etc., calcium oxides, sodiumcarbonate, metallic sodium, in small amounts. Particularly desirablecatalysts are the halides of aluminum, copper, tin, zinc, antimony,arsenic, titanium, boron fluoride, etc.

In some instances, it is desirable to subject the petroleum residuumfirst to an air-blowing, maintaining the temperature at about 450 F. forabout 600 minutes, the material being agitated by the injected air orother suitable means, and then the air-blowing is discontinued and thepolymerizing catalyst is incorporated, e. g. 0.5 per cent AlCls at atemperature of about 250 F. and the heating is maintained at 300400 F.for 20 to 30 minutes. Such air-blowing stage can be operated to somedesired penetration standard, as for instance 92 penetration at 77 F.,and then the polymerization treatment is applied.

As an example: A petroleum residuum having initially a penetration of200 at 77 F., is heated with 1.5 per cent of ferric chloride at atemperature of 350 F., for 60 minutes. The product has a penetration ofat 77 F. and ductility 16 at 39 F. and 72.5 at 77 F.

As another example: A petroleum residuum is air-blown first, and then isheated with 0.9 per cent of boron fluoride in a BF3 ether mixture at atemperature of 400 F. for 15 minutes. The product has a melting point of140 F., ductility at 38 F. 4, and at 77 F. 21, penetration at 32 F, 19,and at 77 F. 47, and at 115 F. 146, and a susceptibility coefficient of2.

As another example: The petroleum residuum is similarly first air-blownas above, and then is heated with 0.5 per cent of FeClz at 400 F. for 30minutes. The product has a melting point of F., ductility at 39 F. 4,and at 77 F. 30, penetration at 32 F. 17, and at 77 F. 51, and at 115 F.192, and susceptibility factor 3.4.

Asphalts produced according to the present invention have particularlyshiny black surfaces, and are not buttery or short in consistency as hasbeen the characteristic of high melting point asphalts from blendedstocks. They also have higher melting points at a given penetration, say77 F., than a customary asphalt, and better susceptibility coefficients.

This application is a division of our application Ser. No. 112,348,filed Nov. 23, 1936 Other modes of applying the principle of theinvention may be employed, change being made as regards the detailsdescribed, provided the features stated in any of the following claims,or the equivalent of such, be employed.

We therefore particularly point out and distinctly claim as ourinvention:

1. A process of making asphalt, which comprises heating with temperaturerise to 350-400 F. and thickening a petroleum residuum in the absence ofinjected air to asphalt-consistency with a small amount of an aluminumchloride catalyst.

2. A process of making asphalt, which comprises air-blowing a petroleumresiduum in the absence of an added catalyst, then thickening thematerial in the absence of injected air to asphalt-consistency byheating with temperature rise to 350-400 F. with a small amount of ahalide of aluminum.

3. A process of making asphalt, which comprises air-blowing a petroleumresiduum in the absence ofan added catalyst, then in the absence ofinjected air thickening the material to asphalt-consistency by heatingwith temperature rise to 350-400 F. with a small amount of an aluminumchloride catalyst.

ROBERT E. BURK. CHARLES H. WHITACRE.

